The invention relates to piling assemblies and to a method of utilization of the piling assemblies to anchor them in the earth.
Especially where heavy ice, wind, and tidal loads are applied to pilings utilized in pier, dock, and marker constructions, conventional tapered pilings do not have a large enough resistance to pull-out pressure, and thus can become loose or un-seated. This is particularly so where the conditions of the bottom into which the piling is driven are especially soft or loose. This can be overcome to a certain extent by driving pilings large and first, however, this increases the resistance during driving and requires that the smaller end of the piling be able to withstand the abuse it will encounter during driving without cracking or splitting. Also, since the thin end of the piling is then above the bottom and water level, it has much less resistance to normal working loads than if the large end of the piling were above bottom and water level. Other attempts have also been made to overcome the problems of piling loosening by providing anchors of a variety of configurations on the pilings, such as shown in U.S. Pat. Nos. 1,429,964 and 2,187,319. Oftentimes, however, prior art anchor constructions unduly increase the resistance to driving of the pilings, and can have a tendency to become hung-up on obstructions, preventing complete penetration of the piling to the desired depth.
According to the present invention, a piling assembly is provided that has substantially increased pull-out resistance compared to conventional pilings, yet has negligibly increased resistance to being driven into almost any bottom texture or terrain, and will not easily become hung-up on obstructions in the bottom surface. Additonally, the assembly according to the present invention has markedly increased extraordinary pull-out pressure resistance so that the probability of being dislodged when water level increases at times when there is surface ice, and other extraordinary conditions, are encountered, is reduced.
The piling assembly according to the present invention comprises an elongated piling having first and second ends, and first, second, third and fourth anchors, each anchor having a circumferential extent less than one-half the circumference of the piling, and extending radially outwardly from the piling, and having a given axial extent. The anchors are attached to the piling so that the first and second anchors are disposed opposite each other at a first position adjacent, but spaced from, the piling first end, and the third and fourth anchors are disposed opposite each other at a second position adjacent, but spaced from, the piling first end a greater distance than the sum of the distance the first position is spaced from the piling first end and the axial length of an anchor. The third and fourth anchors are circumferentially displaced from the first and second anchors around the piling. Preferably, each anchor has a circumferential extent about one-quarter the circumference of the piling, and the third and fourth anchors are circumferentially displaced about 90.degree. from the first and second anchors around the piling.
In the method according to the present invention of driving the piling into the earth, the piling is driven with the small end first, to a desired depth or until an obstruction is encountered by one of the anchors. If an obstruction is encountered the piling is rotated until the anchor encountering the obstruction is no longer in line with the obstruction, and then driving is continued again until the desired piling depth is reached or until another obstruction is encountered, at which time the rotating and further driving steps are repeated.
Each anchor according to the present invention comprises a pocket member of rigid material having an open top communicating with a hollow interior, and a closed bottom, sides, and ends. The pocket member, including the hollow interior thereof, decreases in cross-sectional area from the open top to the bottom thereof, and means are provided for attaching the pocket member to the piling so that the bottom of the anchor is closest to the piling first end. A plurality of flutes are formed in a portion of the anchor defining the open top, the flutes extending from the open top toward the bottom, and these flutes greatly increase extraordinary pull-out pressure resistance by allowing the open top of the pocket to deform as a result of attempted pull-out, thereby increasing resistance further. Once the piling has had about 24-36 hours to set in place, the anchors become filled with material in the bottom into which the piling is driven, and provide enormous resistance to normal pull-out pressures.
Each of the pocket members is defined by a plate and a hollow, open-based, truncated pyramid section extending along the plate. The plate overlaps the truncated pyramid section on the sides and bottom thereof, and a plurality of openings for receiving fasteners are formed in the portions of the plate overlapping the truncated pyramid section, the fasteners attaching the pocket member to the anchor. Openings for receiving fasteners extending through the pyramid section and the plate also may be provided. Preferably the plate is curved, having concave and convex faces with the concave face having a contour corresponding to the circumference of a piling to which it is connected, to the truncated pyramid section being disposed on the convex face of the plate. Most desirably, the pyramid section is a section of the truncated right circular cone. The pocket member may be constructed by welding together two separate pieces of material (i.e. the plate and the pyramid section), or by a press in a single stamping operation.
It is the primary object of the present invention to provide an improved piling anchor, piling assembly, and method of utilization of the piling assembly, having markedly increased resistance to both normal and extraordinary pull-out pressure, but having negligibly increased resistance to driving. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.